Please HELP! Transmission Overheating
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Please HELP! Transmission Overheating
I have a 1995 automatic with the factory transmission. Last night I went on a 1 hr trip to Baton Rouge. The check gauge light came on and when I switch to the trans gauge it read HI Trans at 285 degrees. 
I was averaging about 75-80mph on the interstate when this happened. I pulled over and let it cool down and checked the fluid. I followed the procedure in the owners manual and the levels seemed just a little low so I filled it up some with Techron III. On the way home I left it in drive like the manual states to cool not overdrive and it got up to about 275. I just checked the fluid level this morning and it seems ok. The transmission was just rebuilt summer of 2005 at the dealership. Yes, I will probably bring it back to them but I think they only gave it a 90 day warranty. Please help me with any advice ASAP, this is a daily driver and it's hard to not have the car available. Any trans guys out there? Pete K?
Thanks in advance. I appreciate the help.
I was averaging about 75-80mph on the interstate when this happened. I pulled over and let it cool down and checked the fluid. I followed the procedure in the owners manual and the levels seemed just a little low so I filled it up some with Techron III. On the way home I left it in drive like the manual states to cool not overdrive and it got up to about 275. I just checked the fluid level this morning and it seems ok. The transmission was just rebuilt summer of 2005 at the dealership. Yes, I will probably bring it back to them but I think they only gave it a 90 day warranty. Please help me with any advice ASAP, this is a daily driver and it's hard to not have the car available. Any trans guys out there? Pete K?Thanks in advance. I appreciate the help.
Pro
Joined: Oct 2003
Posts: 732
Likes: 2
From: Baxter MN
I'm not a "transmission guy" and I sure don't have the expertise of PeteK, but may I ask if you had an Aux. ATF cooler installed when you had the rebuild done? If not, thses are fairly inexpensive add-ons that have been used for decades to prolong the life of auto transmissions. I had mine placed directly in front of the power steering cooler and it seems to work well.
Just a thought for the future.
Best wishes.
Glen
Just a thought for the future.
Best wishes.
Glen
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Trans overheat
Yes the engine temperature was fine around 189. The torque converter was just installed new with the trans rebuild and shift kit last summer. I've only done maybe 5 runs in the quarter and the rest has been street driving since. Do they go bad that quick? I'm researching a trans coolers now. I don't know that it will solve whatever the problem is now, but still a great idea. Any advice on a model to go with? One other thing which probably doesnt matter is that my passanger side cat started breaking apart about two months ago, still rattles. I didn't think to see if it was glowing. I'm waiting for the EM header gp with cat delete to be shipped. Could heat from the cat cause underneath to overheat if it's clogged? It doesnt seem like it is clogged though. The car runs fine. I captured the trans and engine data this morning with tts datalog. What is, 1 oil level sw? I saw this on the trans log. Would someone reading the log help out? I can email it or what should I look for?
Thanks again for the help.
Thanks again for the help.
Last edited by rickneworleansla; Jun 17, 2006 at 11:58 AM.
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
I agree with both heat kills transmission, also apart from tranny ext cooler infront of radiator, add 2 qrt extra pan too with fins that will help bring down some temp. Stay focus with pete.
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
trans hot
Pete, Is there a way to test the torque converter for problems? The car seems to be shifting fine under all conditions. I'm going to call the dealership now and find out about the warranty.
I found a pan that I think will work. The TCI 378000, link below. Still looking for a cooler. Could I already have one from the factory? I'll go check the radiator. Even if together both of these lower my temps by 30 degress that wont fix whats wrong. Last night I was at 285. So I would be at 255? Still sounds way too hot for nightime interstate cruisin at 75mph.
http://www.tciauto.com/components/transmission_pans.htm
Thanks
I found a pan that I think will work. The TCI 378000, link below. Still looking for a cooler. Could I already have one from the factory? I'll go check the radiator. Even if together both of these lower my temps by 30 degress that wont fix whats wrong. Last night I was at 285. So I would be at 255? Still sounds way too hot for nightime interstate cruisin at 75mph.
http://www.tciauto.com/components/transmission_pans.htm
Thanks
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Originally Posted by rickreeves1
Pete, Is there a way to test the torque converter for problems? The car seems to be shifting fine under all conditions. I'm going to call the dealership now and find out about the warranty.
I found a pan that I think will work. The TCI 378000, link below. Still looking for a cooler. Could I already have one from the factory? I'll go check the radiator. Even if together both of these lower my temps by 30 degress that wont fix whats wrong. Last night I was at 285. So I would be at 255? Still sounds way too hot for nightime interstate cruisin at 75mph.
http://www.tciauto.com/components/transmission_pans.htm
Thanks
I found a pan that I think will work. The TCI 378000, link below. Still looking for a cooler. Could I already have one from the factory? I'll go check the radiator. Even if together both of these lower my temps by 30 degress that wont fix whats wrong. Last night I was at 285. So I would be at 255? Still sounds way too hot for nightime interstate cruisin at 75mph.
http://www.tciauto.com/components/transmission_pans.htm
Thanks
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
The pan you picked is quite good. One thing to bear in mind though. Cast aluminum pans have a drawback on a street driven car. If you boottom out 1 time, you may knock a hole in them. I like to use the derale pan. It has a slightly deeper sump, holds 2 extra qts(if memory serves) and has the welded in cooling tubes. It is sheetmetal. If you smack it off the road, id will dent like a stock pan.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Originally Posted by Pete K
Every TCI converter that I have used failed quickly. By the 5 th one, I stopped using them. The only accurate way to check it, is to swap it. 285 is way hot. If something internal to the trans is causing the heat, it is already too late.
Not what I was hoping to hear. I received good news when I called another dealership. (Mine was closed) They said transmission rebuild warranties usually last 12 months or 12,000 miles, which should be just barely enough. If I have to get another TC which brand last the longest but is reasonably priced. My TCI may still be under warranty but if they arent that good I don't want to keep having to replace it every year. Checking out the Deral pans now.Thanks
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
Originally Posted by Pete K
The pan you picked is quite good. One thing to bear in mind though. Cast aluminum pans have a drawback on a street driven car. If you boottom out 1 time, you may knock a hole in them. I like to use the derale pan. It has a slightly deeper sump, holds 2 extra qts(if memory serves) and has the welded in cooling tubes. It is sheetmetal. If you smack it off the road, id will dent like a stock pan.
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Originally Posted by sami85L98
Derale 2 qts, thats what i got buddy it has 4 fin tubes too which extends a little 1/4 inch outside of pan, keep's it real cool i found the diff of 15-20 deg less than reguler oil pan.
Thanks
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
I just got the call back from the dealership. They said they took it for a drive and scaned it and everything checked out ok?? hmm... They probably just couldn't drive it long enough. Now What? They suggested I drive it normal for a few days and keep an eye on it. They said as soon as it overheats to bring it to them then. I'm wondering if everything is ok then how can it overheat to 285 degrees. Even yesterday it got to 218 after a 15 minute drive. I thought normal temp was below or around 200. The trans does have the factory coolant system. I'll definately get the new pan, trans flush, and royal purple put in. Hopefully clearance will not be an issue after I lower it. I will first drive it a little hard, no NOS, for the next few days and see what happens. That 12 month warranty has got to be close. I have a feeling I'll be pulling back up to the dealership soon.
Thanks again for all the help and the measurements!
Thanks again for all the help and the measurements!
Last edited by rickneworleansla; Jun 19, 2006 at 04:56 PM.
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
I got to 235 degrees today after a 20 minute drive in hot weather. What is the normal temp range again for an auto trans? They told me to bring it back when it does it again. Letting it get to 285 just doesnt seem safe. I want to get it fixed asap since hurricane season is upon us and I definately dont want to break down while stuck in traffic trying to evacuate. I lost one car last year, cant leave another behind.
Thanks
Thanks
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
Hint: when my original oem transmission went kabooom, coolant temp was 250+ and i flooored it big time, within few blocks (not miles ) a thick very huge white smoke rear of my car and than within a block distance car dont move pull to shoulder, look to see tranny fluid was all over underneath the car, every inch was dipped in tranny oil. So the conclusion tranny was completely toasted cant even rebuilt beyond repairable, from that day my strggle started and end with pete k tranny, wonderful man what a mountain of knowledge and honesty.
hands down to pete k.
hands down to pete k.
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
transmission cooling
New news from the service department. We put it on the lift today and looked underneath. I doesnt look like the derale pan will fit with the convertible crossbrace. The good news is that they identified a blockage in the coolant system for the trans. When I spoke to them last they were checking to see if it was in the coolant lines or in the radiator itself. I'm preparing for the worst and looking for a better radiator now. Hopefully this wont be necessary. My radiator cools the engine just fine. I'm guessing there is another system inside the radiator for the transmission?? Any suggestions. Since I have a coolant system from the factory would an aftermarket unit like the B&M mounted in front the radiator help me out any. How is this different than the factory setup. Would I be doing away with the factory setup and run the lines to the B&M? Or is the B&M cooling the transmission fluid not associated with the radiator. I'm confused! Sorry for the questions but I have no idea how a coolant system on the transmission works. Fortunately all you smart people are always there to help.
Thanks again
Sorry for the questions but I have no idea how a coolant system on the transmission works. Fortunately all you smart people are always there to help.Thanks again
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
Originally Posted by rickreeves1
New news from the service department. We put it on the lift today and looked underneath. I doesnt look like the derale pan will fit with the convertible crossbrace. The good news is that they identified a blockage in the coolant system for the trans. When I spoke to them last they were checking to see if it was in the coolant lines or in the radiator itself. I'm preparing for the worst and looking for a better radiator now. Hopefully this wont be necessary. My radiator cools the engine just fine. I'm guessing there is another system inside the radiator for the transmission?? Any suggestions. Since I have a coolant system from the factory would an aftermarket unit like the B&M mounted in front the radiator help me out any. How is this different than the factory setup. Would I be doing away with the factory setup and run the lines to the B&M? Or is the B&M cooling the transmission fluid not associated with the radiator. I'm confused! Sorry for the questions but I have no idea how a coolant system on the transmission works. Fortunately all you smart people are always there to help.
Thanks again
Sorry for the questions but I have no idea how a coolant system on the transmission works. Fortunately all you smart people are always there to help.Thanks again
Thread Starter
Le Mans Master
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
aha, I understand now. Thanks Pete. They said they pressure tested it and it showed that it was 80% blocked or pressure or something like that. The dealership is the sponsor for my local corvette club. (Crescent City Corvette Club) They take real good care of us over there, plus there's the discount. I'm really hoping it's not something worse. My fingers are crossed. If needed, I'm reading good things about the Dewitt radiators. Sounds like it will be best to do the additional cooler, in line with the radiator cooler, either way.
Thanks
Thanks
Race Director
Joined: Feb 2004
Posts: 12,517
Likes: 19
My factory rad has served me well for 279,000 miles. I also intend to step up to a Dewitt's rad when the time comes. They flat out work. I have a few close friends that have used them. Perfect results.
Solve the trans cooling issue asap. They do not last long when they are above 220 degrees trans fluid temp.
5,000th post! whooo hoooo
Solve the trans cooling issue asap. They do not last long when they are above 220 degrees trans fluid temp.
5,000th post! whooo hoooo
Last edited by Pete K; Jun 26, 2006 at 07:22 PM.